Lumen stent

ABSTRACT

A lumen stent includes a first tube body and a second tube body. The second body is sleeved outside the first body and has at least one end in hermetic connection with the outer surface of the first body. The second body includes a thin film body that covers at least part of the first body and a second radial supporting structure that is disposed in a maximum radius-length region of the thin film body and surrounds the maximum radius-length region. The second radial supporting structure has radius supporting property. After the implantation of the lumen stent, a semi-enclosed gap can be formed between the first body and the second body, or a semi-enclosed gap can be formed between the second body and a tube wall, so that blood flowing into the gap can serve as a filling material and prevent blood from flowing into a tumor body.

FIELD

The present application relates to an implanted medical device, and moreparticularly relates to a luminal stent graft and a luminal stent graftsystem.

BACKGROUND

At present, a luminal stent graft may be adopted to implementendovascular graft exclusion to isolate a diseased region in a humanbody lumen, for example, the luminal stent graft may be adopted toisolate an artery dissection or an arterial aneurysm in a blood vessel.This kind of method has gradually substituted traditional invasiveoperation due to its advantages of a small operation wound, smallintraoperative blood transfusion volume, quick postoperative recovery,short hospital stay, and the like. The luminal stent generally hasradial expandability, and is clung to a vascular cavity wall by usingits radial supporting force so as to be fixed in a lumen. To prevent thestent graft from falling off, the stent graft needs to have a highenough radial supporting force, but the higher radial supporting forceindicates higher rigidity of the radially unfolded stent. However, dueto individual differences, the inner walls of lumens are of differentshapes, and also may have calcified plaques that would change theirshapes; and the luminal stent graft with relatively high rigidity maypossibly result in a poor or decreased ability to cling to a luminalwall, so that a space between the stent graft and a diseased luminalwall may not be completely closed.

For example, with reference to FIG. 1, a plaque 13 on the inner wall ofa lumen 12 may form a clearance 14 between a stent graft 11 and theinner wall of the lumen 12, and blood flow may flow to a tumor cavity ora dissection false cavity through the clearance 14, thus generatingtype-I endoleak. Alternatively, to open up main body blood vessels andbranch blood vessels at the same time, multiple stent grafts are usedcooperatively by adopting a chimney technology, a periscope technologyor a sandwich technology, and then are respectively implanted into themain body blood vessels and the branch blood vessels. For example, withreference to FIG. 2, one end of a main body stent graft 15 and one endof a branch stent graft 16 are abreast implanted into the lumen 12, andthe other end of the main body stent graft 15 is communicated with arelatively large main body blood vessel (not shown in the figure), butthe other end of the branch stent graft 16 is communicated with arelatively small branch blood vessel (not shown in the figure). To makesure that the blood flow flowing into the branch blood vessel isunblocked, the radial supporting force of the branch stent graft 16needs to be greater than that of the main body stent graft 15, and thiswould lead to a situation that portions, which are located at theabreast implanted positions, of the main body stent graft 15 are easierto deform radially to form a clearance 17 among the branch stent graft16, the main body stent graft 15 and the inner wall of the lumen 12,thus generating the type-I endoleak, and the blood flow may flow to thetumor cavity or the dissection false cavity through the clearance 17.

This type-I endoleak may appear in a thoracic aorta, an abdominal aortaor other lumens. Continuous inflow of the blood flow may causecontinuous enlargement of the dissection false cavity or an arterialaneurysm cavity, and finally result in a serious consequence of breakageof the dissection false cavity or the arterial aneurysm cavity, so thatthe endovascular graft exclusion may fail. Therefore, to enhance thesurgical effect and increase the healing success rate, it is veryimportant for the luminal stent graft used in the endovascular graftexclusion to avoid the type-I endoleak between the stent graft and thelumen as much as possible.

SUMMARY

To solve the technical problems and overcome the shortcomings in theprior art, the present application provides a luminal stent graftcapable of avoiding formation of an endoleak.

The present application adopts a technical scheme shown and describedherein to solve the technical problem: a luminal stent graft isprovided, including a first tubular body and a second tubular body; thesecond tubular body is sleeved outside the first tubular body, and atleast one end of the second tubular body is sealingly connected with theouter surface of the first tubular body; the second tubular bodyincludes a graft covering at least one portion of the first tubular bodyand a second radial supporting structure which is arranged in a maximumradial length region of the graft and surrounds the maximum radiallength region; and the second radial supporting structure has radialsupportability. In the luminal stent graft according to the embodimentof the present application, the first tubular body includes at least onefirst radial supporting structure distributed along a circumferentialdirection of the first tubular body.

In the luminal stent graft according to the embodiment of the presentapplication, in a naturally unfolded state, at the same position in aradial supporting section, the radial length of the second radialsupporting structure is 1.3 times to 3 times the radial length of thefirst radial supporting structure.

In the luminal stent graft according to the embodiment of the presentapplication, in the naturally unfolded state, the radial length of thesecond radial supporting structure is more than that of the first radialsupporting structure by 2 mm to 30 mm.

In the luminal stent graft according to the embodiment of the presentapplication, the radial deformability of the second radial supportingstructure is greater than that of the first radial supporting structure.

In the luminal stent graft according to the embodiment of the presentapplication, under the action of the same radial force, a radial lengthvariation of the second radial supporting structure is greater than thatof the first radial supporting structure; or under the action of thesame radial force, a radial length change rate of the second radialsupporting structure is greater than that of the first radial supportingstructure; or in case of the same radial change rate or the same radialvariation, a radial external force exerted on the first radialsupporting structure is greater than that exerted on the second radialsupporting structure.

In the luminal stent graft according to the embodiment of the presentapplication, the second radial supporting structure is a waveformring-like object; and in the naturally unfolded state, a maximum width mof any waveform of the waveform ring-like object along a circumferentialdirection and a perimeter D of the second tubular body at the waveformaccord with a condition that m is less than or equal to D/8 or m is lessthan or equal to D/10 or m is less than or equal to D/12 or m is lessthan or equal to D/13 or m is less than or equal to D/14.

In the luminal stent graft according to the embodiment of the presentapplication, the second radial supporting structure is of a meshedstructure including multiple grids; and in a naturally unfolded state, amaximum width m1 of any grid along the circumferential direction and theperimeter D of the second tubular body at the grid accord with acondition that m1 is less than or equal to D/12 or m1 is less than orequal to D/13 or m1 is less than or equal to D/14.

In the luminal stent graft according to the embodiment of the presentapplication, in the portion covered by a graft, the first tubular bodyfurther includes a first graft covering the first radial supportingstructure.

In the luminal stent graft according to the embodiment of the presentapplication, one end of the graft is sealingly connected with the firsttubular body, and the other end of the graft is open; and the maximumradial length region of the graft is located near to an opening of theopen end, or is located at the middle portion of the graft.

In the luminal stent graft according to the embodiment of the presentapplication, two ends of the graft are sealingly connected with thefirst tubular body, and the maximum radial length region of the graft islocated at the middle portion of the graft.

In the luminal stent graft according to the embodiment of the presentapplication, at least one end of the first tubular body has multipleconvex pieces extending in parallel to the longitudinal axis of thefirst tubular body, and a gap is reserved between two adjacent convexpieces.

In the luminal stent graft according to the embodiment of the presentapplication, the first tubular body includes four wave loops arrayed insequence along a longitudinal central axis direction of the firsttubular body, and the four wave loops are connected through squareconnecting rings.

In the luminal stent graft according to the embodiment of the presentapplication, the first tubular body includes barrel-shaped inner grafts,wave loops and annular outer grafts; the wave loops are arranged betweenthe barrel-shaped inner graft and the annular outer graft in a clampingmanner; and at least part of wave crests and/or wave troughs of the waveloops are exposed outside.

In the luminal stent graft according to the embodiment of the presentapplication, a graft is arranged on the first tubular body; and a holepenetrating through the graft is formed in a portion, which is near tothe end portion of the first tubular body, on the graft or the waveloop, which is close to the end portion of the first tubular body, ofthe first tubular body is not completely covered by the graft.

After the luminal stent graft according to the embodiment of the presentapplication is implanted, a semi-closed clearance may be formed betweenthe first tubular body and the second tubular body, or a semi-closedclearance is formed between the second tubular body and a lumen wall;and a blood flowing into the clearance may be used as a filler materialto occlude a type-I endoleak channel, thus avoiding the blood fromflowing into a tumor body or a dissection.

BRIEF DESCRIPTION OF THE DRAWINGS

A further description will be made to the present application below inconjunction with accompanying drawings and embodiments. In thesedrawings:

FIG. 1 is a schematic diagram of a single luminal stent graft implantedinto a lumen having a plaque in the prior art;

FIG. 2 is a schematic diagram of two luminal stent grafts implanted intoa lumen cooperatively in the prior art;

FIG. 3 is a schematic diagram of a structure of an example luminal stentgraft according to a first embodiment of the present application;

FIG. 4 is an axial section diagram of a single luminal stent graftimplanted into a lumen according to the first embodiment of the presentapplication;

FIG. 5 is a schematic diagram of multiple turns of waveform ring-likeobjects of one example of a second tubular body in the first embodiment;

FIG. 6 is a schematic diagram of multiple turns of waveform ring-likeobjects of a second tubular body in another specific implementationmode;

FIG. 7 is a schematic diagram of a flat plate pressing method-based teston a luminal stent graft according to a second embodiment of the presentapplication;

FIG. 8 is a schematic diagram of a flat plate pressing method-based teston the luminal stent graft according to the second embodiment of thepresent application;

FIG. 9 is a radial section diagram of a luminal stent graft in anaturally unfolded state according to the second embodiment of thepresent application;

FIG. 10 is a radial section diagram of the radially compressed luminalstent graft in FIG. 9;

FIG. 11 is a schematic diagram of a single luminal stent graft implantedinto a lumen having a plaque according to the second embodiment of thepresent application;

FIG. 12 is a schematic diagram of a luminal stent graft according to athird embodiment of the present application;

FIG. 13A is a schematic diagram of a specific structure of the luminalstent graft of FIG. 12;

FIG. 13B is an axial section diagram of the luminal stent graft, whichis implanted into a lumen, in FIG. 13A;

FIG. 14 is a schematic diagram of a luminal stent graft according to afourth embodiment of the present application;

FIG. 15 is a schematic diagram of an example structure of a luminalstent graft according to a fifth embodiment of the present application;

FIG. 16 is a schematic diagram of another example structure of a luminalstent graft according to the fifth embodiment of the presentapplication;

FIG. 17 is a schematic diagram of a cut meshed structure of the secondtubular body in FIG. 16;

FIG. 18 is a partial enlarged view of FIG. 17;

FIG. 19 is a schematic diagram of a luminal stent graft system accordingto a sixth embodiment of the present application;

FIG. 20 is a radial section diagram of the proximal end of the luminalstent graft system in FIG. 19;

FIG. 21 is a schematic diagram of another example structure of a luminalstent graft system according to the sixth embodiment of the presentapplication;

FIG. 22 is a schematic diagram of a luminal stent graft system accordingto a seventh embodiment of the present application;

FIG. 23 is a radial section diagram of a portion near to the renalartery after the luminal stent graft system in FIG. 22 is implanted;

FIG. 24 is a radial section diagram of a portion near to the iliumartery after the luminal stent graft system in FIG. 22 is implanted;

FIG. 25 is a schematic diagram of a luminal stent graft provided by aneighth embodiment of the present application;

FIG. 26 is a schematic diagram of a luminal stent graft provided by aninth embodiment of the present application;

FIG. 27 is a schematic diagram of a first tubular body in FIG. 26;

FIG. 28 is an enlarged view of a portion P in FIG. 27;

FIG. 29 is a diagram of a state after the first tubular body in FIG. 26is bent;

FIG. 30 is a schematic diagram of a luminal stent graft provided by atenth embodiment of the present application;

FIG. 31 is a schematic diagram of a luminal stent graft provided by aneleventh embodiment of the present application;

FIG. 32 is a schematic diagram of multiple wave loop groups, which arenot covered by the annular outer grafts, of a first tube cavity of theluminal stent graft in FIG. 31.

DETAILED DESCRIPTION

For the purpose of making technical features, objectives and effects ofthe present application clearer, now a detailed description will be madeto specific implementation modes of the present application withreference to the drawings.

First Embodiment

With reference to FIG. 3, a luminal stent graft 2 according to the firstembodiment of the present application includes a first tubular body 21and a second tubular body 22; the second tubular body 22 is sleevedoutside the first tubular body 21, and covers at least one portion ofthe first tubular body 21; and one end of the second tubular body 22 issealingly connected with the peripheral surface of the first tubularbody 21.

In this embodiment, the first tubular body 21 has radial expandability,may be compressed under the action of an external force, and restores aninitial shape through self-expansion or mechanical expansion (such asballoon dilatation expansion) and keeps the initial shape after theexternal force is withdrawn, so that after being implanted into a lumen,the first tubular body 21 may cling to the lumen wall through its radialsupporting force to be fixed in the lumen. The first tubular body 21includes a first radial supporting structure 211 arranged on the wholetubular body, for example, the first radial supporting structure 211 maybe made of a memory alloy material (for example a nickel-titaniumalloy), thereby having self-expansion capacity. The first radialsupporting structure 211 may include multiple turns of waveformring-like objects distributed along an axial direction, or may be of ameshed structure formed by weaving a metal wire, or may be of a cutmeshed structure formed by cutting a metal tube. A person of ordinaryskill in the art can select a proper first radial supporting structure211 according to a desire or requirement, so, for the sake of brevity,no further details are described herein. In addition, at least a region,which is not covered by the second tubular body 22, of the first tubularbody 21 also includes a first graft 212; and the first graft 212 may bea PET (polyethylene terephthalate) film or a PTFE(polytetrafluoroethylene) film, and may cover the first radialsupporting structure 211 in a suturing or hot melting way.

The second tubular body 22 has radial expandability. Namely it may becompressed under the action of an external force, restores to an initialshape through self-expansion or mechanical expansion (such as balloondilatation expansion), and keeps the initial shape after the externalforce is withdrawn, so that after being implanted into the lumen, thesecond tubular body 22 may cling to the lumen wall through its radialsupporting force. The second tubular body 22 includes a graft 222 and asecond radial supporting structure 221 which is arranged in a maximumradial length region L of the graft 222 and surrounds the maximum radiallength region L; and the second tubular body 22 has the above-mentionedradial expandability, or radial supportability or radial supportingforce, due to its second radial supporting structure 221. For example,the second radial supporting structure 221 may be made of a memory alloymaterial (for example a nickel-titanium alloy), thereby havingself-expansion capacity. The second radial supporting structure 221 mayinclude multiple turns of waveform ring-like objects distributed alongan axial direction, or may be a mesh structure formed by weaving metalwire, or may be of a cut mesh structure formed by cutting a metal tube.A person of ordinary skill in the art can select a proper second radialsupporting structure 221 according to a desire or requirement, so, forthe sake of brevity, no further details are described herein. The graft222 may be a PET film or a PTFE film, and may cover the second radialsupporting structure 221 in a suturing or hot melting manner. It can beunderstood that under the same condition, the radial supporting force ofthe second radial supporting structure is greater than that of thegraft.

One end of the second tubular body 22 and the first tubular body 21 maybe sealingly connected via hot melting of the graft 222 and the firstgraft 212, and also may be sealingly connected by suturing the graft 222onto the first graft 212. A person of ordinary skill in the art canselect a proper sealing way according to a desire or requirement, so,for the sake of brevity, no further details are described herein.

In the example of a luminal stent graft, as shown in FIG. 3, one end ofthe graft 222 is sealingly connected with the first tubular body 21, andthe other end of the graft 222 is open; and the maximum radial lengthregion L of the graft 222 is located near to an opening of the open end,and of course, the maximum radial length region L may be located at themiddle portion of the graft 222.

With reference to FIG. 4, one end of the second tubular body 22 is anopen tube orifice; as the second radial supporting structure 221 has theradial supporting force or radial supportability, and is arranged in themaximum radial length region of the graft 222, the second tubular body22 (namely the graft 222) may be attached to the inner wall of a lumen12 after being implanted, and an effective clearance 20 is formedbetween the second tubular body 22 and the first tubular body 21; whenflowing into the luminal stent graft 2 from the proximal end 23, a bloodalso flows into the clearance 20 at the same time; and as the tubeorifice in the other end of the second tubular body 22 is closed, theblood flowing into the clearance 20 may achieve a sealing and fillingeffect, thereby reducing and even avoiding blood flow which flows intothe clearance formed between the second tubular body 22 and the innerwall of the lumen and cutting off a channel or an opening that may formtype-I endoleak, and this part of blood will be directly thrombosed inthe clearance 20 to make the sealing and filling effect better. In thesealing process, no other sealing or filling materials need to be addedinto the luminal stent graft 2 in advance or after the luminal stentgraft 2 is implanted, but sealing also may be realized only throughinflowing blood from normal blood circulation, so that no extrabiological risk caused by the sealing or filling materials will beincreased.

In the specific structure of the luminal stent graft 2, in a naturallyunfolded state, at the same position (namely the same radial section) ofthe maximum radial length region L of the graft 222, the radial lengthof the second radial supporting structure 221 is 1.3 times to 3 timesthe radial length of the first radial supporting structure 211, so thatat this position, a clearance space is formed between the first tubularbody 21 and the second tubular body 22.

Alternatively, at the same position of the maximum radial length regionL of the graft 222, the radial length of the second radial supportingstructure 221 is more than that of the first radial supporting structure211 by 2 mm to 30 mm, so that at this position, a clearance space isformed between the first tubular body 21 and the second tubular body 22.In one embodiment, when the radial length of the first tubular body 21is 20 mm to 48 mm, a corresponding luminal stent graft is generallyapplied to aorta positions including an ascending aorta, an aorta arch,a thoracic descending aorta and an abdominal aorta; at the moment, theradial length of the second radial supporting structure 221 at the sameposition is more than that of the first radial supporting structure 211by 2 mm to 20 mm; when the radial length of the first tubular body 21 is4 mm to 20 mm, a corresponding luminal stent graft is generally appliedto a branch blood vessel such as an arch branch, a renal artery and aniliac artery; at the moment, the radial length of the second radialsupporting structure 221 at the same position is more than that of thefirst radial supporting structure 211 by 3 mm to 30 mm.

As the second tubular body has the radial expandability. Namely it maybe compressed under the action of an external force, restores to theinitial shape through self-expansion or mechanical expansion (such asballoon dilatation expansion), and keeps the initial shape after theexternal force is withdrawn, a radial length difference between thefirst tubular body and the second tubular body or a radial length ratioof the first tubular body to the second tubular body may be valuedwithin a relatively large range. If the radial length difference betweenthe first tubular body and the second tubular body or the radial lengthratio of the first tubular body to the second tubular body needs to berelatively small, for example, if the radial length difference is up to2 mm, 3 mm or 4 mm, the first tubular body and the second tubular bodymay not be attached together due to their radial expandability, so thatthe clearance space still exists, and may be kept unblocked; and if theradial length difference between the first tubular body and the secondtubular body or the radial length ratio of the first tubular body to thesecond tubular body needs to be relatively large, for example, if theradial length difference is more than 10 mm, the second tubular bodystill may effectively cling to the lumen wall, and may not turn overunder impact of the blood flow. Therefore, the luminal stent graftaccording to the embodiment of the present application is wide inapplication range and high in stability of blocking the leak.

In one mode of the second radial supporting structure 221, withreference to FIG. 5, the second radial supporting structure 221 includesat least one turn of waveform ring-like object 2221, and the figureshows four turns of waveform ring-like objects 2221, but this is onlyused as an example, and is not intended to limit the presentapplication. A person of ordinary skill in the art can select a propernumber of waveform ring-like objects 2221 according to a requirement.The waveform ring-like objects 2221 may be formed by winding a metalwire, for example, they may be formed by winding a memory alloy(including a nickel-titanium alloy) wire into a preset waveform; a metalwire with a wire diameter (namely the diameter) of 0.05 mm to 0.4 mm maybe selected; and the waveform may be a Z-shaped wave, a U-shaped wave ora sine wave and the like. Or, the waveform ring-like objects also may beformed by cutting a metal tube, and the wire diameter of a metal rodforming the waveform ring-like objects is 0.05 mm to 0.4 mm. This figureshows a schematic diagram of the second radial supporting structure 221which is unfolded axially, so that the axially unfolded width D here isthe perimeter of a portion, which is at the second radial supportingstructure 221, of the second tubular body 22.

In addition, by the adoption of the metal wire with the same wirediameter, if the radial length of the second radial supporting structure221 is larger, the equivalent wire diameter of the second radialsupporting structure 221 is smaller, and vice versa. It can be seen fromhere that an effect of reducing the wire diameter may be achieved byincreasing the radial length of the second radial supporting structure221. Under a circumstance that other conditions are the same, if theequivalent wire diameter of a radial supporting structure is smaller,the radial deformability of the radial supporting structure is higher.

For example, in one implementation mode, if the first radial supportingstructure and the second radial supporting structure have same waveformstructures and are formed by metal wires having the same wire diameters,the second radial supporting structure has the equivalent wire diameterless than that of the first radial supporting structure due to itsrelatively large radial length, so that the radial deformability of thesecond radial supporting structure is greater than that of the firstradial supporting structure.

In one embodiment, when the radial length of the second radialsupporting structure 221 is 4 mm to 20 mm, the wire diameter of a formedwaveform is 0.05 mm to 0.32 mm; when the radial length of the secondradial supporting structure 221 is 20 mm to 50 mm, the wire diameter ofa wound waveform is 0.1 mm to 0.35 mm; and when the radial length of thesecond radial supporting structure 221 is 50 mm to 80 mm, the wirediameter of a wound waveform is 0.2 mm to 0.4 mm. The metal wire withinthe above-mentioned wire diameter range has relatively high bendingflexibility, so that a waveform ring-like object formed by winding themetal wire has relatively high radial deformability.

Any turn of waveform ring-like object 2221 includes multiple waveforms,and adjacent waveforms are connected to each other. Any waveformincludes two interconnected supporting pieces which are adjacent to eachother and form a certain included angle, and a maximum width m of thewaveform along the circumferential direction and a perimeter D, whichcorresponds to the waveform ring-like object with the waveform, of thesecond tubular body 22 accord with a condition that m is less than orequal to D/12, and m ranges from 1.5 mm to 8 mm. In one embodiment, mmay be equal to the maximum relative circumferential distance betweentwo adjacent supporting pieces.

It can be seen from the above that in one circumferential radialsupporting structure, for example, in one turn of circumferentiallydistributed waveform ring-like object, the maximum circumferentialdistance between two adjacent supporting pieces accords with a conditionthat m is less than or equal to D/12, for example, also may accord witha condition that m is less than or equal to D/8, or m is less than orequal to D/10, or m is less than or equal to D/13, or m is less than orequal to D/14. Although the maximum circumferential distance (namely themaximum width of the waveform along the circumferential direction) maynot provide enough radial supporting force to fix the radial supportingstructure in the lumen, the provided radial supporting force is highenough to enable the radial supporting structure to be attached to thelumen wall; and as the maximum circumferential distance is relativelysmall, the radial supporting structure may be embedded into a tiny orsmall gap to be attached to the inner walls of lumens in various shapesand avoid the formation of the endoleak. The radial supporting force forfixing the luminal stent graft in the lumen may be provided by the firstradial supporting structure in the first tubular body.

To further improve the deformability of the second radial supportingstructure complying with the inner wall of the lumen, the waveformheight of each of the above-mentioned waveform ring-like objects may beset to be 2 mm to 8 mm. To be specific, when the radial length of thesecond radial supporting structure 221 is 4 mm to 20 mm, the waveformheight is 2 mm to 6 mm; when the radial length of the second radialsupporting structure 221 is 20 mm to 50 mm, the wire diameter of a woundwaveform is 3 mm to 7 mm; and when the radial length of the secondradial supporting structure 221 is 50 mm to 80 mm, the wire diameter ofa wound waveform is 4 mm to 8 mm. If the waveform height is smaller, thecapacity of complying with the shape deformation of the inner wall ofthe lumen is higher.

At least one waveform of each waveform ring-like object 2221 has aninternal fillet 2222, a maximum width n of the internal fillet 2222along the circumferential direction accords with a condition that n isless than or equal to 1.5 mm. If the value of n is smaller, thedeformability of the second tubular body 22 for complying with the innerwall of the lumen is higher, and the clearance filling capacity ishigher, so that the capacity for blocking the endoleak is higher.

The second radial supporting structure 221 may include multiple turns ofwaveform ring-like objects 2221 distributed along an axial direction.There are many ways of distributing the multiple turns of waveformring-like objects 2221. For example, with reference to FIG. 5, thesecond radial supporting structure 221 includes at least two adjacentturns of waveform ring-like objects 2221 which are isolated mutually andhave no overlapped regions. Namely an axial distance is reserved betweenany wave crest of one turn of waveform ring-like object and any wavetrough of the other adjacent turn of waveform ring-like object, whereinthe minimum axial distance may be less than 3 mm. To avoid shortening ofthe second tubular body 22, connecting rods 2223 also may be arranged toconnect the multiple waveform ring-like objects 2221. For anotherexample, with reference to FIG. 6, the second radial supportingstructure 221 at least includes two adjacent turns of waveform ring-likeobjects 2221, wherein the waveforms of one turn of waveform ring-likeobject are embedded into the waveforms of the other adjacent turn ofwaveform ring-like object. Namely, an axial distance between any wavecrest of one turn of a waveform ring-like object and one of the closestwave crests of the other adjacent turn of the waveform ring-like objectis less than the waveform height of this turn of waveform ring-likeobject. The waveform ring-like objects 2221 in the figure are taken asan example, and one waveform ring-like object is embedded into the otheraxially adjacent waveform ring-like object according to an embeddingdepth H1 which accords with a condition that H1 is less than or equal toH/3, where H is the waveform height (namely the axial distance betweenone wave crest and one wave trough) of the embedded waveform ring-likeobject 2221.

Second Embodiment

On the basis of the first embodiment, according to a luminal stent graftof the second embodiment, further in the maximum radial length region Lof the graft 222, the radial deformability of the second radialsupporting structure 221 is greater than that of the first radialsupporting structure 211. That is to say, under the action of the sameradial force (the sizes and the directions of radial acting forces andthe acting time are all the same), the radial length variation of thefirst radial supporting structure 211 in the radial supporting sectionis less than that of the second radial supporting structure 221 at thesame position; or under the action of the same radial force (the sizesand the directions of the radial acting forces and the acting time areall the same), the radial length change rate of the first radialsupporting structure 211 in the radial supporting section is less thanthat of the second radial supporting structure 221 at the same position;and this change rate is a ratio of the radial length variation to anoriginal radial length.

Under the action of the same radial force, a larger radial lengthvariation or a larger radial length change rate indicates higher radialdeformability and lower radial supportability of a radial supportingstructure, and vice versa. Alternatively, in the above-mentioned maximumradial length region L, in case of the same radial change rate or thesame radial variation, a radial external force exerted on the firstradial supporting structure 211 is greater than the radial externalforce exerted on the second radial supporting structure 221. A higherradial force exerted on indicates a lower radial deformability and ahigher radial supportability, and vice versa.

With reference to FIG. 7, a flat plate pressing method may be adopted,namely the tubular bodies 21 and 22 may be clamped in the radialsupporting section along a tangential direction of the circumference ofthe radial supporting section by adopting two mutually parallel flatplates 18. In a test process, the two flat plates are always kept inparallel. Equal radial forces F are applied to the flat plates 18 totest the radial length variations ΔR or the radial length change ratesΔR/R of the first radial supporting structure 211 and the second radialsupporting structure 221 in the radial supporting section, and thedirections of the radial forces F are parallel to certain diameters,which are located at pressed portions, of the tube bodies 21 and 22. Or,when the above-mentioned flat plate pressing method may be adopted tocompress the first radial supporting structure 211 in the radialsupporting section or the second radial supporting structure 221 in theradial supporting section from an original size R (FIG. 7) to R/2 (FIG.8), a measured radial force F1 to be applied is used for evaluating theradial supporting force or the radial supportability, and thisevaluation result is equivalent to an evaluation result obtained on thebasis of the radial length variation or the radial length change rate,wherein in a situation of the same radial acting condition (the actingtime and the acting way of the radial force are the same), a smallervalue of the radial force F1 applied to compressing the tubular bodyfrom the original size R to R/2 indicates higher radial deformabilityand lower radial supportability of the tubular body, and vice versa.

The above-mentioned flat plate pressing method is only one example testmethod, and is not intended to be a limitation to the presentapplication. A person of ordinary skill in the art can adopt any propermethod to carry out a test equivalent to the flat plate pressing method,for example, a radial acting force also may be uniformly applied to thecircumferential direction of the lumen for testing. To be specific, aradial supporting force tester RX550-100 of the Machine Solution Inc(MSI) Company may be adopted.

In one specific implementation mode of the present application, underthe action of the same radial force, the radial length variation of thesecond radial supporting structure 221 in the radial supporting sectionis 1.05 times to 10 times the radial length variation of the firstradial supporting structure 211 in the radial supporting section, andfor example may be two to 5 times. Or, under the action of the sameradial force, the radial length change rate of the second radialsupporting structure 221 in the radial supporting section is 1.05 timesto 10 times the radial length change rate of the first radial supportingstructure 211 in the radial supporting section, and for example may betwo to 5 times. Or, under the same test condition, the radial force tobe applied to compressing the first radial supporting structure 211 fromthe original size R to R/2 is 1.05 times to 10 times the radial force tobe applied to compressing the second radial supporting structure 221from the original size R to R/2, and for example may be two to 5 times.

When compared with the first radial supporting structure 211, when thesecond radial supporting structure 221, has a radial deformability thatis extremely high, its radial supportability is low, which leads to asituation that the second radial supporting structure may not becompletely radially unfolded in a releasing process, thereby causing awrinkling or collapsing phenomenon, so that the radial deformability ofthe second radial supporting structure 221 will not generally exceed 10times of the radial deformability of the first radial supportingstructure 211. Of course, if the radial deformability of the secondradial supporting structure 221 has little difference from that of thefirst radial supporting structure 211, an endoleak still may be formedafter the second tubular body 22 is implanted. Therefore, the radialdeformability of the second radial supporting structure 221 is generallygreater than 1.05 times of the radial deformability of the first radialsupporting structure 211. To be specific, the radial deformability ofthe second radial supporting structure 221 is two to 5 times, such as 3times and 4 times, the radial deformability of the first radialsupporting structure 211.

It should be noted that the radial deformability described herein is aradial reacting force generated by a tubular body on an external radialacting force when the tubular body is pressed by the external radialacting force, for example, when the first tubular body 21 or the secondtubular body 22 is pressed radially by a lumen after being implanted.Under the same external radial acting force, higher radial reactingforce generated by the tubular body indicates that this tubular body hasrelatively low radial deformability and relatively high radialsupporting force or relatively high radial supportability, and viceversa. For example, when the first radial supporting structure 211 andthe second radial supporting structure 221 are implanted into the sameposition and are pressed radially by the same lumen, the radial reactingforce generated by the first radial supporting structure 211 isrelatively high, and the radial reacting force generated by the secondradial supporting structure 221 is relatively low, so that the firstradial supporting structure 211 has higher radial supporting force orhigher radial supportability and lower radial deformability than thesecond tubular body 22. If a tubular body does not have theabove-mentioned radial expandability by itself, for example the onewhich only has a graft and does not have a radial supporting structure,it will be compressed under the external radial acting force, but afterthe external force is withdrawn, it may not restore to its initial shapeand keep the initial shape, so that the radial reacting force generatedby this tubular body on the external radial acting force may bebasically ignored, and it is unnecessary to compare the radialsupporting force or the radial supportability of the tubular body ofthis structure.

In addition, the second radial supporting structure 221 is arrangedalong the circumferential direction, and further, the second radialsupporting structure 221 is continuously arranged along thecircumferential direction. After implantation, when a certain portion ofthe second radial supporting structure 221 deforms under the radialacting force, the second radial supporting structure 221 may transmitthis deformation or pressure along the circumferential direction,thereby realizing that the second tubular body complies with the shapeof the lumen wall and clings to the lumen wall, and the second radialsupporting structure 221 may actively fill the small gaps around toavoid formation of a blood flow leak channel between the second tubularbody and the lumen wall.

It can be known from the above description that after the luminal stentgraft 2 is implanted into a human body lumen, in its radial supportingsection, the luminal stent graft 2 includes the first tubular body 21and the second tubular body 22 covering the first tubular body 21; thefirst tubular body 21 may cling to the lumen wall due to its relativelylow radial deformability, so that the whole luminal stent graft may befixed in the lumen to avoid displacement or falling off from the lumen;the second tubular body 22 has the radial supporting force due to thesecond radial supporting structure 221, and may be radially expanded tobe attached to the lumen wall, so that no clearance will be formedbetween the lumen wall and the second tubular body 22 by insufficientradial supporting force. Furthermore, as the radial deformability of thesecond tubular body 22 is higher than that of the first tubular body 21,when the second tubular body 22 and the first tubular body 21 areimplanted into the same lumen position at the same time, the secondtubular body 22 complies with the shape deformation of the inner wall ofthe lumen more easily, thereby avoiding formation of the clearancebetween the second tubular body 22 and the inner wall of the lumen andcutting off a channel or an opening that may form the type-I endoleak.

For example, with reference to FIG. 9, in a natural state, namely astate that no external radial force or external radial pressure exists,the first tubular body 21 (namely the first radial supporting structure)and the second tubular body 22 (namely the second radial supportingstructure) may be both radially expanded and unfolded. With reference toFIG. 10, under the external radial force or external radial pressure,for example, when the luminal stent graft is placed at a certain portionof a to-be-treated blood vessel, the first tubular body 21 will keep theradial shape basically unchanged under the radial pressure of thevascular wall to avoid displacement or falling off of the luminal stentgraft 2; and the second tubular body 22 will comply with the deformationunder the radial pressure of the blood vessel and keep radial expansionand unfolding to avoid deformation such as radial collapse, sinking, andturnover.

With reference to FIG. 11, if the luminal stent graft 2 is implantedinto a lumen having a plaque 13, under a radial force or radial pressuregenerated by the lumen, the first tubular body 21 keeps the radial shapebasically unchanged to avoid displacement or falling off, and maintainsa blood flow channel unblocked; the second tubular body 22 may complywith the deformation at the plaque 13, and is still attached to theinner wall of the lumen and the surface of the plaque by its radialexpandability, so that the clearance formed between the first tubularbody 21 and the inner wall of the lumen is filled, and at the same time,no clearance will be formed among the second tubular body 22, the innerwall of the lumen and the surface of the plaque, thus cutting off thechannel or the opening that may form the type-I endoleak and avoidingthe blood from flowing into a tumor body or a dissection 18.

Third Embodiment

With reference to FIG. 12, the difference from the luminal stent graftof the first embodiment is that the tube orifice, which is close to theproximal end 23, of a second tubular body 22 of a luminal stent graft 2according to the third embodiment is hermitically connected with theperipheral surface of a first tubular body 21, thus forming a closedtube orifice, and the tube orifice, which is close to the distal end 24,of the second tubular body 22 is open. The second tubular body 22 islocated near to the proximal end 23 of the first tubular body 21, but aperson of ordinary skill in the art should know that this figure is onlyused as an example and is not a limitation to the present application. Aperson of ordinary skill in the art can arrange the second tubular body22 near to the distal end 24 of the first tubular body 21 based on theinstruction of the present application.

With reference to FIG. 13A and FIG. 13B, to be specific, the secondtubular body 22 may further include a straight tube section 221 a, aconical tube section 222 a and a connecting section 223 a; theconnecting section 223 a is sealingly connected with the first tubularbody 21; the conical tube section 222 a is connected with the connectingsection 223 a and the straight tube section 221 a; and the maximumradial length region of the second tubular body is located in thestraight tube section 221 a, so that a second radial supportingstructure (which is not shown in the figure) is at least arranged in thestraight tube section 221 a.

After implantation, the second tubular body 22 complies with thedeformation of the inner wall of a lumen 12; the connecting section 223a and the conical tube section 222 a may possibly form a clearance 20together with the inner wall of the lumen 12 as their radial lengths arerelatively small; the straight tube section 221 a has a relatively largeradial length, and may be completely attached to the inner wall of thelumen 12 through the second radial supporting structure; if the shape ofa certain position, where the straight tube section 221 a is implanted,on the wall of the lumen 12 is not smooth, the straight tube section 221a may comply with the shape deformation, but other portions of thestraight tube section 221 a still may be attached to the inner wall ofthe lumen 12 by their radial expandability. When flowing into theluminal stent graft 2, blood flows into the clearance 20 possibly formedby the connecting section 223 a and the conical tube section 222 atogether with the inner wall of the lumen 12 at the same time, or alsomay flow into a clearance (which is not shown in the figure in detail)formed by the straight tube section 221 a and the inner wall of thelumen 12. However, the portion, which is attached into the lumen 12, ofthe straight tube section 221 a will prevent further inflow of the bloodby its radial supporting force, and the blood left in all theabove-mentioned clearances are thrombosed, and then forms a seal,thereby cutting off a channel or an opening that may form type-Iendoleak and avoiding the blood from flowing into a tumor body or adissection 18.

Fourth Embodiment

With reference to FIG. 14, the difference from the luminal stent graftof the first embodiment is that two tube orifices of a second tubularbody 22 of a luminal stent graft 2, according to the fourth embodiment,are both sealingly connected with the peripheral surface of a firsttubular body 21, thus forming two closed tube orifices. At the moment,if the two tube orifices of the second tubular body 22 are sealed, thisluminal stent graft is similar to that of the second embodiment, andsimilarly, after implantation, a channel or an opening that may formtype-I endoleak also may be cut off. In this sealing process, no othersealing or filling materials need to be added into the luminal stentgraft 2 in advance or after the luminal stent graft 2 is implanted, butsealing may be realized only through inflowing blood from normal bloodcirculation, so that no extra biological risk caused by the sealing orfilling materials will be increased.

Fifth Embodiment

A luminal stent graft of the fifth embodiment is approximately the sameas the luminal stent graft of the first embodiment, but the differenceis that a second radial supporting structure includes a mesh structure,for example a woven mesh structure or a cut mesh structure. For example,with reference to FIG. 15, the radial supporting structure of a secondtubular body 22 includes the woven mesh structure; and with reference toFIG. 16, the radial supporting structure of the second tubular body 22includes the cut mesh structure.

With reference to FIG. 17 and FIG. 18, the second radial supportingstructure 221 includes the cut mesh structure which has multiple grids2224. The mesh structure may be formed by cutting a metal net tube, forexample it may be integrally formed by carrying out laser cutting on amemory alloy (including a nickel-titanium alloy) net tube, and the metalnet tube may be 0.05 mm to 0.4 mm in thickness. During cutting, thediameter of each of connecting rods 2225 forming the grids 2224 in anencircling manner may be 0.05 mm to 0.4 mm. To be specific, when theradial length of the second radial supporting structure 221 is 4 mm to20 mm, the diameter of each connecting rod 2225 is 0.05 mm to 0.32 mm;when the radial length of the second radial supporting structure 221 is20 mm to 50 mm, the diameter of each connecting rod 2225 is 0.1 mm to0.35 mm; and when the radial length of the second radial supportingstructure 221 is 50 mm to 80 mm, the diameter of each connecting rod2225 is 0.2 mm to 0.4 mm. As a metal wire within the above-mentionedwire diameter range has relatively high bending flexibility, a waveformring-like object formed by winding the metal wire has relatively highradial deformability. The maximum width m1 of any grid 2224 formed bycutting and the perimeter D of the second tubular body 22 at this grid2224 accord with a condition that m1 is less than or equal to D/12. Tobe specific, when the radial length of the second radial supportingstructure 221 is 4 to 20 mm, the maximum width m1 and the perimeter Daccord with the condition that m1 is less than or equal to D/12, and m1ranges from 1.5 mm to 5 mm. When the radial length of the second radialsupporting structure 221 is 20 mm to 50 mm, the maximum width m1 and theperimeter D accord with a condition that m1 is less than or equal toD/13, and m1 ranges from 1.5 mm to 7 mm. When the radial length of thesecond radial supporting structure 221 is 50 mm to 80 mm, the maximumwidth m1 and the perimeter D accord with a condition that m1 is lessthan or equal to D/14, and m1 ranges from 1.5 mm to 8 mm. If m1 issmaller, the filling effect is better.

To further improve the deformability of the second radial supportingstructure for complying with the inner wall of the lumen, the maximumlength of the above-mentioned grid along an axial direction is 4 mm to16 mm. To be specific, when the radial length of the second radialsupporting structure 221 is 4 mm to 20 mm, the maximum length of thegrid along the axial direction is 4 to 12 mm. When the radial length ofthe second radial supporting structure 221 is 20 mm to 50 mm, themaximum length of the grid along the axial direction is 6 mm to 14 mm.When the radial length of the second radial supporting structure 221 is50 mm to 80 mm, the maximum length of the grid along the axial directionis 8 mm to 16 mm.

At least one grid 2224 of the meshed structure has an internal fillet2222, the maximum width n1 of the internal fillet 2222 along thecircumferential direction accords with a condition that n1 is less thanor equal to 1.5 mm. If the n1 value is smaller, the deformability of thesecond tubular body 22 for complying with the inner wall of the lumen ishigher, and the clearance filling capacity is higher, so that thecapacity of blocking the endoleak is higher.

Sixth Embodiment

The sixth embodiment provides a luminal stent graft system. The luminalstent graft system includes at least one luminal stent graft 2 accordingto any one of embodiments 1 to 4, where multiple luminal stent grafts 2may be implanted into a lumen cooperatively, or one or multiple luminalstent grafts 2 and other existing luminal stent grafts which do not havesecond radial supporting structures are implanted into the lumencooperatively. In order to facilitate distinguishing variousembodiments, the luminal stent grafts 2 according to the embodiments ofthe present application are collectively called a first luminal stentgraft 2 below, and the other existing luminal stent grafts which do nothave the second radial supporting structures may be collectively calleda second luminal stent graft 3. There is at least one first luminalstent graft 2, namely there may be one or two first luminal stentgrafts, and even more first luminal stent grafts. For example, oneconventional second luminal stent graft 3 and one first luminal stentgraft 2 according to the embodiment of the present application may becooperatively applied to a chimney technology, or a periscopetechnology, or a sandwich technology, for example. For another example,one conventional second luminal stent graft 3 and two first luminalstent grafts 2 according to the embodiments of the present applicationmay be cooperatively applied to an abdominal aorta, wherein the secondluminal stent graft 3 is implanted into the abdominal aorta, and the twofirst luminal stent grafts 2 are respectively implanted into a renalartery. The above situations are only used as examples, and are notlimitations to the present application, so that persons of ordinaryskill in the art can select a proper number of and a proper type ofluminal stent grafts to form the luminal stent graft system forcooperative implantation according to a specific condition of animplantation lumen based on the instruction of the present applicationto guarantee unblocked blood flow.

With reference to FIG. 19, the aorta arch 191 generally has three branchblood vessels, for example, a blood flow channel may be rebuilt at thisposition by adopting the chimney technology. An arrow is used in thefigure to provide a blood flow direction, and it has been defined thatthe blood flows goes from the proximal end to the distal end in theabove contents. After implantation, with reference to FIG. 20 together,directions of openings in the proximal end of the first luminal stentgraft 2 and the proximal end of the second luminal stent graft 3 areconsistent, and the first luminal stent graft 2 and the second luminalstent graft 3 are arranged in the aorta arch blood vessel 191 side byside, wherein the first luminal stent graft 2 is a luminal stent graftwhich has a first tubular body 21 and a second tubular body 22 accordingto the embodiment of the present application; the second luminal stentgraft 3 may be one of the first luminal stent graft 2, and also may bean existing luminal stent graft which does not have a second radialsupporting structure. In this figure, the second luminal stent graft 3is a conventional stent graft, for example, it is may be a straighttubular stent graft. The distal end of the first luminal stent graft 2extends into one branch blood vessel, such as a left subclavian artery192, so that blood can flow into the branch blood vessel from the aortaarch blood vessel 191 through the first luminal stent graft 2, thusrebuilding a branch blood vessel channel. As a brief schematic, FIG. 20shows the first luminal stent graft 2 including the first tubular body21 and the second tubular body 22, wherein the second tubular body 22covers part of a proximal end region of the first tubular body 21, butdoes not cover the proximal end face of the first tubular body 21; andthe specific structure of the first luminal stent graft 2 is as shown inFIG. 3. The proximal end of the first luminal stent graft 2 and theproximal end of the second luminal stent graft 3 are arranged side byside; the proximal end face of the second tubular body 22 issubstantially flush with the proximal end face of the second luminalstent 3; and the first tubular body 21 relatively extends and protrudestowards the proximal end.

With reference to FIG. 20, after implantation, and under the radialcompression action of the lumen wall, the first luminal stent graft 2and the proximal end region of the second luminal stent graft 3 radiallypress each other in the aorta arch blood vessel 191; in the radialsupporting section, the second luminal stent graft 3 serving as a mainbody stent complies with the deformation under the pressure of the firstluminal stent graft 2 serving as a branch stent; to guarantee unblockedblood flow in the branch blood vessel, the first tubular body 21 of thefirst luminal stent graft 2 has relatively high radial supporting force,and may avoid lumen loss in a pressing process; and the second tubularbody 22 may simultaneously comply with the shape deformation of thelumen wall and the shape deformation of the second luminal stent graft 3due to its relatively low radial supporting force, thereby forming aclearance 20 between the first tubular body 21 and the second tubularbody 22. A type-I endoleak channel between the main body stent and thebranch stent in the prior art is filled with the clearance 20; as oneend of the clearance 20 is open, and the other end of the clearance 20is closed, blood flow flowing into the clearance 20 may be used as asealing and filling material for blocking the type-I endoleak channel toavoid the blood flow from entering a tumor body or a dissection; and thesecond tubular body 22 is unblocked, so that the blood flow cansuccessfully flow into the branch blood vessel. Further, when the bloodflow rushes at the semi-closed clearance 20, a vortex is formed underthe action of the pressure, and then the blood flow direction ischanged, so that the blood can flow into the first tubular body 21favorably, thereby promoting unblocked circulation of the blood flow inthe branch blood vessel and guaranteeing the flow rate of the blood flowin the branch blood vessel.

With reference to FIG. 21, in another example, the blood vessel channelmay be rebuilt by adopting the periscope technology. The distal end ofthe second luminal stent graft 3 serving as the main body stent and theproximal end of the first luminal stent graft 2 serving as the branchstent may be arranged side by side; an arrow in the figure shows a bloodflow direction; for a single luminal stent graft here, blood alwaysflows from the proximal end of the luminal stent graft to the distalend. To be specific, the first luminal stent graft 2 includes a firsttubular body 21 and a second tubular body 22; the second tubular body 22covers part of a proximal end region of the first tubular body 21, butdoes not cover the proximal end face of the first tubular body 21. Theproximal end of the first luminal stent graft 2 and the distal end ofthe second luminal stent graft 3 are arranged side by side; the proximalend face of the second tubular body 22 is basically flush with thedistal end face of the second luminal stent graft 3; and the firsttubular body 21 extends and protrudes relative to the second tubularbody 22. After implantation, under the radial compression action of alumen (such as an aorta arch 191) wall, a semi-closed clearance (whichis not shown in the figure) is formed among the distal end of the secondluminal stent graft 3, the first tubular body 21, the second tubularbody 22 and the lumen wall, and a semi-closed clearance (which is notshown in the figure) is also formed between the first tubular body 21and the second tubular body 22, thereby preventing generation of atype-I endoleak channel and avoiding blood from flowing into a tumorbody or a dissection. In addition, the blood flow may inversely enterthe proximal end of the first luminal stent graft 2 from the distal endof the second luminal stent graft 3, as shown in the arrow A. Also, inthis case, the blood flow generates relatively low impact force on theabove-mentioned semi-closed clearances, thus further preventingformation of type-I endoleak.

Seventh Embodiment

With reference to FIG. 22, the luminal stent graft according to theembodiment of the present application also may be applied to anabdominal aorta 193. If the stent is implanted into the abdominal aorta193, two branch blood vessels at a renal artery and/or an iliac arteryshould be considered according to the shape of a tumor body or adissection 18. An arrow in the figure is a blood flow direction, and ithas been defined above that for a single luminal stent graft, blood flowflows from the proximal end to the distal end. Multiple first luminalstent grafts 42 and 43 and one second luminal stent graft 41 may beadopted for cooperative implantation, wherein the first luminal stentgrafts 42 and 43 are luminal stent grafts having first tube bodies andsecond tube bodies according to the embodiments of the presentapplication, and the second luminal stent graft 41 may be a luminalstent graft which is of the same type as the first luminal stent grafts42 and 43 or may be a different luminal stent graft. In this figure, thesecond luminal stent graft 41 is a conventional covered stent, such as astraight tube type covered stent.

With reference to FIG. 22 and FIG. 23, at renal arteries 194 and 195,the two first luminal stent grafts 42 and 43 and the one second luminalstent graft 41 are implanted cooperatively; directions of openings inthe proximal ends of the two first luminal stent grafts 42 and 43 andthe proximal end of the second luminal stent graft 41 are consistent,and the first luminal stent grafts 42 and 43 and the second luminalstent graft 41 are arranged in the abdominal aorta blood vessel 193 sideby side; the distal end of each of the two first luminal stent grafts 42and 43 extends into one branch blood vessel respectively, namely theright renal artery 194 or the left renal artery 195, so that blood mayflow into the branch blood vessels from the abdominal aorta blood vessel193 through the first luminal stent grafts 42 and 43.

To be specific, the first luminal stent graft 42 includes a firsttubular body 421 and a second tubular body 422; the second tubular body422 covers part of a proximal end region of the first tubular body 421,but does not cover the proximal end face of the first tubular body 421.The proximal end of the first luminal stent graft 42 and the proximalend of the second luminal stent graft 41 are arranged side by side; theproximal end face of the second tubular body 422 is basically flush withthe proximal end face of the second luminal stent graft 41; and thefirst tubular body 421 relatively extends and protrudes towards theproximal end. Similarly, the first luminal stent graft 43 includes afirst tubular body 431 and a second tubular body 432; the second tubularbody 432 covers part of a proximal end region of the first tubular body431, but does not cover the proximal end face of the first tubular body431. The proximal end of the first luminal stent graft 43 and theproximal end of the second luminal stent graft 41 are arranged side byside; the proximal end face of the second tubular body 43 is basicallyflush with the proximal end face of the second luminal stent graft 41;and the first tubular body 431 relatively extends and protrudes towardsthe proximal end.

With reference to FIG. 23, after implantation, under the radialcompression action of the lumen wall of the abdominal aorta blood vessel193, the first luminal stent graft 42 and the proximal end region of thesecond luminal stent graft 41 radially press each other in the abdominalaorta blood vessel 193; in the radial supporting section, the secondluminal stent graft 41 serving as a main body stent complies with thedeformation under the pressure of the first luminal stent graft 42serving as a branch stent; to guarantee unblocked blood flow in thebranch blood vessel, the first tubular body 421 of the first luminalstent graft 42 has relatively high radial supporting force, and mayavoid lumen loss in a pressing process; and the second tubular body 422may comply with the shape deformation of the lumen wall and the shapedeformation of the second luminal stent graft 41 due to its relativelylow radial supporting force, thereby forming a clearance 420 between thefirst tubular body 421 and the second tubular body 422. A type-Iendoleak channel between the main body stent and the branch stent in theprior art is filled with the clearance 420; as one end of the clearance420 is open, and the other end of the clearance 420 is closed, bloodflow flowing into the clearance 420 may be used as a sealing and fillingmaterial for plugging the type-I endoleak channel; and the secondtubular body 422 is unblocked, so that the blood flow may successfullyflow into the branch blood vessel. Further, when the blood flow rushesat the semi-closed clearance 420, a vortex is formed under the action ofthe pressure, and then the blood flow direction is changed, so that theblood may flow into the first tubular body 421 favorably, therebypromoting unblocked circulation of the blood flow in the branch bloodvessel and guaranteeing the flow rate of the blood flow in the branchblood vessel. Similarly, a clearance 430 may be also formed between thefirst tubular body 431 and the second tubular body 432 of the firstluminal stent graft 43, and the type-I endoleak channel between the mainbody stent and the branch stent in the prior art is filled with theclearance 430.

With reference to FIG. 22 and FIG. 24, at iliac arteries 196 and 197,the two first luminal stent grafts 44 and 45 are implantedcooperatively; directions of openings in the proximal ends of the twofirst luminal stent grafts 44 and 45 are consistent, and the firstluminal stent grafts 44 and 45 are arranged in the abdominal aorta bloodvessel 193 side by side; the distal end of each of the two first luminalstent grafts 44 and 45 extends into one branch blood vesselrespectively, namely the right iliac artery 196 or the left iliac artery197, so that blood may flow into the branch blood vessels 196 and 197from the abdominal aorta blood vessel 193 through the first luminalstent grafts 44 and 45.

To be specific, the first luminal stent graft 44 includes a firsttubular body 441 and a second tubular body 442; the second tubular body442 covers part of a proximal end region of the first tubular body 441,but does not cover the proximal end face of the first tubular body 441.The first luminal stent graft 45 includes a first tubular body 451 and asecond tubular body 452; the second tubular body 452 covers part of aproximal end region of the first tubular body 451, but does not coverthe proximal end face of the first tubular body 451. The proximal endsof the two first luminal stent grafts 44 and 45 are arranged side byside, and their proximal end faces are basically flush with each other,for example, the proximal end faces of the two first tube bodies 441 and451 are basically flush with each other, and/or the proximal end facesof the two second tube bodies 442 and 452 are basically flush with eachother.

With reference to FIG. 24, after implantation, under the radialcompression action of the lumen wall of the abdominal aorta blood vessel193, the two first luminal stent grafts 44 and 45 radially press eachother in the abdominal aorta blood vessel 193; in the radial supportingsection, the two first tube bodies 441 and 451 deform little due totheir relatively high radial supporting forces, and the two second tubebodies 442 and 452 may comply with the shape deformation of the lumenwall and the shape deformation of the first tube bodies due torelatively low radial supporting force, thereby forming clearances, suchas clearances 440 and 450, between the corresponding first tube bodiesand the corresponding second tube bodies. As one end of each clearanceis open, and the other end of the clearance is closed, blood flowflowing into the clearance may be used as a sealing and filling materialfor plugging a type-I endoleak channel to avoid the blood from flowinginto the a tumor body or a dissection and ensure that the blood flow maysuccessfully flow into the two first tube bodies.

Eighth Embodiment

With reference to FIG. 25, a luminal stent graft 2 according to theseventh embodiment of the present application is approximately similarto the luminal stent graft 2 of the first embodiment of the presentapplication, and includes a first tubular body 21 and a second tubularbody 22. The second tubular body 22 is sleeved outside the first tubularbody 21, and covers at least one portion of the first tubular body 21;and one end of the second tubular body 22 is sealingly connected withthe peripheral surface of the first tubular body 21. The differencebetween the luminal stent graft 2 of this embodiment and the luminalstent graft 2 of the first embodiment is as follows: each end of thefirst tubular body 21 of the eighth embodiment has multiple convexpieces 27 extending in parallel to the longitudinal axis of the firsttubular body 21, and a gap 28 is reserved between two adjacent convexpieces 27. The convex pieces 27 may be formed in a way of, for example,removing the graft between two adjacent wave crests in a wave loop,which is closest to the end portion of the first tubular body 21, of thefirst tubular body 21 in the first embodiment. The wave loop in thepresent application is a waveform ring-like object surrounding thelongitudinal central axis of the first tubular body 21.

After the luminal stent graft 2 in this embodiment is implanted into ahuman body by adopting a method as shown in FIG. 19, FIG. 21 or FIG. 22,even if the side wall of the blood flow inlet end of the first tubularbody 21 in this embodiment is gathered together into the lumen in ablood vessel due to the pressure applied by the main body stent graftand the vascular wall, the blood flow also may flow into the firsttubular body 21 from the gap 28 between the two convex pieces 27 at theblood flow inlet end of the first tubular body 21 in this embodiment,thereby avoiding the risk that the blood flow may not enter acorresponding branch blood vessel from the blood flow inlet end of thefirst tubular body which is closed by the pressure of the main bodystent graft and the vascular wall, and improving the safety and theeffectiveness of the operation. It should be noted that in otherembodiments, for example, a hole is formed in the graft (for example:the graft between the first wave loop counted from left to right and theblood flow inlet end or the graft between the first wave loop countedfrom left to right and the second wave loop) near to the blood flowinlet end (namely the left side end of the first tubular body 21 in FIG.3) of the first tubular body 21 as shown in FIG. 3, and penetratesthrough the graft, or the first wave loop, which is close to the bloodflow inlet end (namely the left side end of the first tubular body 21 inFIG. 3), of the first tubular body 21 as shown in FIG. 3 is notcompletely covered by the graft (namely multiple wave crests, which faceto the left side, of the first wave loop counted from left to right areexposed); and it also ensures that even under a condition that an inletof the blood flow inlet end is blocked by a blood vessel, there is stilla blood flow flowing towards a branch blood vessel through the firsttubular body.

It should be noted that in FIG. 25, to display the structure of thefirst tubular body 21 more clearly, a simple dotted line is speciallyadopted to express the second tubular body 22. As a matter of fact, thesecond tubular body 22 in this embodiment is the same as the secondtubular body 22 in the first embodiment, and the first tubular body 21in this embodiment is approximately similar to the first tubular body 21in the first embodiment, but the difference is as follows: two ends ofthe first tubular body 21 in this embodiment have multiple convex pieces27, that is to say, the first tubular body 21 in this embodiment may beobtained by removing a film between every two adjacent wave crests in awave loop, which is closest to the corresponding end portion, at each oftwo ends of the first tubular body 21 in the first embodiment, namelythe luminal stent graft 2 in this embodiment may be obtained by removingthe film between every two adjacent wave crests in the wave loop, whichis closest to the corresponding end portion, at each end of the firsttubular body 21 of the luminal stent graft 2 in the first embodiment.

It can be understood that in other embodiments, according to an actualrequirement, multiple convex pieces 27 may be only formed at the bloodflow inlet end of the first tubular body 21. That is to say, no convexpieces 27 are arranged at the blood flow outlet end of the first tubularbody 21.

It also can be understood that in other embodiments, a graft between onepair of adjacent wave crests in a wave loop, which is closest to theblood flow inlet end, of the first tubular body 21 in the firstembodiment may not be removed according to a requirement as long asgrafts between at least two pairs of adjacent wave crests in themultiple wave crests are removed to form the multiple convex pieces. Italso can be understood that in other embodiments, at least one holepenetrating through each convex piece also may be formed in the convexpiece. It also can be understood that in other embodiments, the wavecrests of the convex pieces also may not be covered by the graft, andthis may be designed according to an actual requirement.

Ninth Embodiment

With reference to FIG. 26, a luminal stent graft 2 according to theninth embodiment of the present application is approximately similar tothe luminal stent graft 2 of the seventh embodiment of the presentapplication, and includes a first tubular body 21 and a second tubularbody 22. The second tubular body 22 is sleeved outside the first tubularbody 21, and covers at least one portion of the first tubular body 21;and one end of the second tubular body 22 is sealingly connected withthe peripheral surface of the first tubular body 21. The differencebetween the luminal stent graft 2 of the ninth embodiment of the presentapplication and the luminal stent graft in the eighth embodiment is asfollows: except for wave loops at two end sockets, each turn of waveloop 23 of the first tubular body 21 in this embodiment is arrangedbetween one annular outer graft 219 and one barrel-shaped inner graft210 in a clamping manner; moreover, the wave crests of each wave loop218 are exposed outside, and the wave troughs of each wave loop 218 areall wrapped by the corresponding annular outer graft 219 and thecorresponding barrel-shaped inner graft 210 (with reference to FIG. 27and FIG. 28). The annular outer grafts 219 and the barrel-shaped innergrafts 210 may be PET (polyethylene terephthalate) films or PTFE(polytetrafluoroethylene) films, and may clamp the wave loops of thefirst tubular body 21 in a suturing or hot melting way.

With reference to FIG. 29, as the wave crests of each wave loop areexposed outside (that is to say, the wave crests of each wave loop arenot wrapped by the annular outer graft 219 and the barrel-shaped innergraft 210), the wave crests of each wave loop may be separated from theannular outer graft 219 and the barrel-shaped inner graft 210 (that isto say, the wave crests of each wave loop may be up-warped relative tothe annular outer graft 219 and the barrel-shaped inner graft 210);therefore, when the first tubular body 21 is bent, on the lessercurvature side, in two adjacent wave loops, one wave loop may beoverlapped with the other wave loop, thereby improving the softness ofthe first tubular body 21. In the present application, the lessercurvature side is the side having a small bending radius when the firsttubular body 21 is bent. In addition, it is precisely because the wavecrests on the lesser curvature side are exposed outside that it isdifficult for the wave crests on the lesser curvature side to puncturethe barrel-shaped inner grafts in the bending process, thus prolongingthe service life of the first tubular body 21.

It can be understood that in other embodiments, the wave crests on thelesser curvature side of the first tubular body 21 also may be onlyexposed to achieve the aim of the present application.

Tenth Embodiment

With reference to FIG. 30, a luminal stent graft 2 according to thetenth embodiment of the present application is approximately similar tothe luminal stent graft 2 of the eighth embodiment of the presentapplication, and includes a first tubular body 21 and a second tubularbody 22. The second tubular body 22 is sleeved outside the first tubularbody 21, and covers at least one portion of the first tubular body 21;and one end of the second tubular body 22 is sealingly connected withthe peripheral surface of the first tubular body 21. The differencebetween the luminal stent graft 2 of the tenth embodiment of the presentapplication and the luminal stent graft in the eighth embodiment is asfollows: except for wave loops at two end sockets, each turn of waveloop 218 of the first tubular body 21 in this embodiment is arrangedbetween one annular outer graft 219 and one barrel-shaped inner graft210 in a clamping manner, and the annular outer graft 219 is locatedbetween the wave crests and the wave troughs of the wave loop 218clamped by it; and the wave crests and the wave troughs of the wave loop218 are all exposed outside. The annular outer grafts 219 and thebarrel-shaped inner grafts 210 may be PET films or PTFE films, and mayclamp the wave loops of the first tubular body 21 in a suturing or hotmelting way.

As the wave crests and the wave troughs of each wave loop are exposedoutside (that is to say, the wave crests and the wave troughs of eachwave loop are not wrapped by the annular outer graft 219 and thebarrel-shaped inner graft 210), the wave crests and the wave troughs ofeach wave loop may be separated from the annular outer graft 219 and thebarrel-shaped inner graft 210 (that is to say, the wave crests and thewave troughs of each wave loop may be all up-warped relative to theannular outer graft 219 and the barrel-shaped inner graft 210).Therefore, when the first tubular body 21 is bent, on the lessercurvature side, in two adjacent wave loops, one wave loop may beoverlapped with the other wave loop, thereby improving the softness ofthe first tubular body 21. In addition, it is precisely because the wavecrests and the wave troughs of the wave loops are exposed outside thatit is difficult for the wave crests or the wave troughs of the waveloops to puncture the barrel-shaped inner grafts in the bending process,thus prolonging the service life of the first tubular body 21.

In one embodiment, the width of each annular outer graft 219 along thelongitudinal central axial line direction of the first tubular body 21is greater than or equal to ⅓ of a distance between the wave crests andthe wave troughs of the wave loop clamped by the annular outer graft 219along the longitudinal central axial line direction of the first tubularbody 21, and less than or equal to ⅔ of the distance between the wavecrests and the wave troughs of the wave loop clamped by the annularouter graft 219 along the longitudinal central axial line direction ofthe first tubular body 21 to ensure that the wave loop may not beseparated from the graft and the wave crests and the wave troughs of thewave loop are exposed outside.

It can be understood that in other embodiments, the wave crests on thelesser curvature side of the first tubular body 21 also may be onlyexposed to achieve the aim of the present application.

Eleventh Embodiment

With reference to FIG. 31, a luminal stent graft 2 according to theeleventh embodiment of the present application is approximately similarto the luminal stent graft 2 of the first embodiment of the presentapplication, and includes a first tubular body 21 and a second tubularbody 22. The second tubular body 22 is sleeved outside the first tubularbody 21, and covers at least one portion of the first tubular body 21;and one end of the second tubular body 22 is sealingly connected withthe peripheral surface of the first tubular body 21. The differencebetween the luminal stent graft 2 of this embodiment and the luminalstent graft 2 of the first embodiment is as follows: the first tubularbody 21 of the eleventh embodiment includes barrel-shaped inner grafts210, a first wave loop group 211, a second wave loop group 212, a thirdwave loop group 213, a fourth wave loop group 214 and annular outergrafts 219 arranged on the wave loop groups, wherein the second waveloop group 212 is located between the first wave loop group 211 and thethird wave loop group 213; the third wave loop group 213 is locatedbetween the second wave loop group 212 and the fourth wave loop group214; and the four wave loop groups are connected through squareconnecting rings 215, that is to say, the first wave loop group 211, thesecond wave loop group 212, the third wave loop group 213 and the fourthwave loop group 214 are arrayed in sequence along the longitudinalcentral axis direction of the first tubular body 21. The annular outergrafts 219 and the barrel-shaped inner grafts 210 may be PET films orPTFE films, and may clamp the wave loops of the first tubular body 21 ina suturing or hot melting way. It can be understood that the first waveloop group 211, the second wave loop group 212, the third wave loopgroup 213 and the fourth wave loop group 214 form one portion of a barestent of the first tubular body 21.

With reference to FIG. 32 together, the first wave loop group 211includes a first wave loop 211 a, a second wave loop 211 b and a thirdwave loop 211 c which are connected. The first wave loop 211 a has twoadjacent relatively high wave crests 2111, multiple relatively low wavecrests 2112 and multiple wave troughs 2113; the multiple relatively lowwave crests 2112 are parallel and level to one another in thelongitudinal central axis direction of the first tubular body 21; themultiple wave troughs 2113 are parallel and level to one another in thelongitudinal central axis direction of the first tubular body 21; andthe multiple relatively low wave crests 2112 are located between themultiple relatively high wave crests 2111 and the multiple wave troughs2113. Multiple wave crests of the second wave loop 211 b, multiple wavecrests of the third wave loop 211 c and the multiple relatively low wavecrests 2112 are parallel and level in the longitudinal central axisdirection of the first tubular body 21. Multiple wave troughs of thesecond wave loop 211 b, multiple wave troughs of the third wave loop 211c and the multiple wave troughs 2113 are parallel and level in thelongitudinal central axis direction of the first tubular body 21.

The second wave loop group 212 includes a first wave loop 212 a, asecond wave loop 212 b and a third wave loop 212 c which are connected.The first wave loop 212 a has one relatively high wave crest 2121,multiple relatively low wave crests 2122 and multiple wave troughs 2123;the multiple relatively low wave crests 2122 are parallel and level toone another in the longitudinal central axis direction of the firsttubular body 21; the multiple wave troughs 2123 are parallel and levelto one another in the longitudinal central axis direction of the firsttubular body 21; and the multiple relatively low wave crests 2122 arelocated between the relatively high wave crest 2121 and the multiplewave troughs 2123. The relatively high wave crest 2121 is hooked andwound with the wave troughs 2113 between the two adjacent relativelyhigh wave crests 2111 of the first wave loop 211 a to form a whole toconnect the first wave loop 211 a with the first wave loop 212 a, namelyto connect the first wave loop group 211 with the second wave loop group212. Multiple wave crests of the second wave loop 212 b, multiple wavecrests of the third wave loop 212 c and the multiple relatively low wavecrests 2122 are parallel and level in the longitudinal central axisdirection of the first tubular body 21. Multiple wave troughs of thesecond wave loop 212 b, multiple wave troughs of the third wave loop 212c and the multiple wave troughs 2123 are parallel and level in thelongitudinal central axis direction of the first tubular body 21.

The third wave loop group 213 includes a first wave loop 213 a, a secondwave loop 213 b and a third wave loop 213 c, which are connected. Thefirst wave loop 213 a has two adjacent relatively high wave crests 2131,multiple relatively low wave crests 2132 and multiple wave troughs 2133;the multiple relatively low wave crests 2132 are parallel and level toone another in the longitudinal central axis direction of the firsttubular body 21; the multiple wave troughs 2133 are parallel and levelto one another in the longitudinal central axis direction of the firsttubular body 21; and the multiple relatively low wave crests 2132 arelocated between the multiple relatively high wave crests 2131 and themultiple wave troughs 2133. In the two relatively high wave crests 2131of the first wave loop 213 a, the wave crest 2131 on the left side ishooked and wound with the wave trough 2113 on the left side, which isclosest to the relatively high wave crest 2121 of the first wave loop212 a, and the wave crest 2131 on the right side is hooked and woundwith the wave trough 2113 on the right side, which is closest to therelatively high wave crest 2121 of the first wave loop 212 a to connectthe first wave loop 212 a with the first wave loop 213 a, namely toconnect the second wave loop group 212 with the third wave loop group213. Multiple wave crests of the second wave loop 213 b, multiple wavecrests of the third wave loop 213 c and the multiple relatively low wavecrests 2132 are parallel and level in the longitudinal central axisdirection of the first tubular body 21. Multiple wave troughs of thesecond wave loop 213 b, multiple wave troughs of the third wave loop 213c and the multiple wave troughs 2133 are parallel and level in thelongitudinal central axis direction of the first tubular body 21.

The fourth wave loop group 214 includes a first wave loop 214 a, asecond wave loop 214 b and a third wave loop 214 c, which are connected.The first wave loop 214 a has one relatively high wave crest 2141,multiple relatively low wave crests 2142 and multiple wave troughs 2143;the multiple relatively low wave crests 2142 are parallel and level toone another in the longitudinal central axis direction of the firsttubular body 21; the multiple wave troughs 2143 are parallel and levelto one another in the longitudinal central axis direction of the firsttubular body 21; and the multiple relatively low wave crests 2142 arelocated between the relatively high wave crest 2141 and the multiplewave troughs 2143. The relatively high wave crest 2141 is hooked andwound with the wave troughs 2133 between the two adjacent relativelyhigh wave crests 2131 of the third wave loop 213 a to form a whole toconnect the third wave loop 213 a with the fourth wave loop 212 a,namely to connect the first wave loop group 211 with the second waveloop group 212. Multiple wave crests of the second wave loop 214 b,multiple wave crests of the third wave loop 214 c and the multiplerelatively low wave crests 2142 are parallel and level in thelongitudinal central axis direction of the first tubular body 21. Thelongitudinal central axis directions of the first tubular body 21,multiple wave troughs of the second wave loop 214 b, multiple wavetroughs of the third wave loop 214 c and the multiple wave troughs 2143are parallel and level.

Therefore, the first wave loop group 211, the second wave loop group212, the third wave loop group 213, and the fourth wave loop group 214are connected into a whole through the square connecting rings 215.

It can be understood that in each wave loop group, the second wave loopand/or the third wave loop may be omitted as long as each wave loopgroup has the first wave loop such that the four wave loop groups may beconnected through the square connecting rings. It also can be understoodthat in the four wave loop groups, or in one, two or three wave loopgroups, the second wave loop and/or the third wave loop may be omittedas long as each wave loop group has the first wave loop such that thefour first wave loops may be connected through the square connectingrings. It also can be understood that the first wave loop group 211 alsomay not include the first wave loop and/or the second wave loop, and atthe moment, the wave troughs of the third wave loop also may be hookedand wound with the relatively high wave crest of the second wave loopgroup to connect the first wave loop group with the second wave loopgroup.

Each annular outer graft 219 is also arranged on each wave loop group,and is located between the wave crests and the wave troughs of the waveloop group clamped by it, and the wave crests and the wave troughs ofthe wave loop group are all exposed outside.

As the wave crests and the wave troughs of each wave loop group areexposed outside (that is to say, the wave crests and the wave troughs ofeach wave loop group are not wrapped by the annular outer graft 219 andthe barrel-shaped inner graft 210), the wave crests and the wave troughsof each wave loop group may be separated from the annular outer graft219 and the barrel-shaped inner graft 210 (that is to say, the wavecrests and the wave troughs of each wave loop group may be all up-warpedrelative to the annular outer graft 219 and the barrel-shaped innergraft 210); therefore, when the first tubular body 21 is bent, on thelesser curvature side, in two adjacent wave loop groups, one wave loopgroup may be overlapped with the other wave loop group, therebyimproving the softness of the first tubular body 21. In addition, it isprecisely because the wave crests and the wave troughs of the wave loopgroups are exposed outside that it is difficult for the wave crests orthe wave troughs of the wave loop groups to puncture the barrel-shapedinner grafts in the bending process, thus prolonging the service life ofthe first tubular body 21.

in this embodiment, the wave loops at two ends of the first tubular body21 are all covered by the annular outer grafts 219, that is to say, thewave loops at the two ends are all covered by the annular outer grafts219 and the barrel-shaped inner grafts 210, so that the softness of thefirst tubular body 21 may be better improved. In addition, in thisembodiment, the wave loop groups may be connected into a whole throughthe annular outer grafts 219 and the barrel-shaped inner grafts 210, andalso may be connected into a whole through the square connecting rings215, so that the stability of the first tubular body 21 is improved, thesoftness of the first tubular body 21 is also increased, and the servicelife of the first tubular body 21 is prolonged.

It can be understood that in other embodiments, the bare stent of thefirst tubular body also may include a first wave loop group, a secondwave loop group, a third wave loop group and a fourth wave loop groupwhich are connected through square connecting rings.

Above all, the luminal stent graft according to each embodiment of thepresent application includes the first tubular body and the secondtubular body which covers at least one part of the radial supportingsection of the first tubular body; after the luminal stent graft isimplanted, the semi-closed clearance may be formed between the firsttubular body and the second tubular body, or the semi-closed clearancemay be formed between the second tubular body and the lumen wall; andthe blood flowing into the above-mentioned clearances may be used as thefilling material to plug the type-I endoleak channel, thus avoiding theblood from flowing into the tumor body or the dissection.

In addition, the first tubular body and the second tubular body bothhave the radial supportabilities, namely the radial supporting forces,so that after the luminal stent graft is implanted into the lumen, thefirst tubular body and the second tubular body still may be attached tothe lumen wall by their radial supporting forces under the radialcompression of the lumen wall; and at the same time, under the impact ofthe blood flow, the first tubular body and the second tubular body maykeep radial supporting shapes to avoid occurrence of the deformationsuch as wrinkling, introversion and collapse, and particularly to ensurethat no deformation occurs on the proximal end face of the luminal stentgraft, thereby avoiding blocking the blood flowing into the lumen.

In addition, the second tubular body has relatively high radialdeformability when compared with the first tubular body, so that underthe radial compression action of the lumen wall, the first tubular bodymay guarantee no lumen loss and keep unblocked blood flow, and thesecond tubular body may adapt to the deformations of the lumen wall andthe first tubular body when attached to the lumen wall; and formation ofthe type-I endoleak is prevented through the clearance between the firsttubular body and the second tubular body or the clearance between thesecond tubular body and the lumen wall.

In addition, in the stent system according to the embodiment of thepresent application, the luminal stent graft according to theembodiments of the present application may cooperate with otherconventional luminal stent grafts, or multiple luminal stent graftsaccording to the embodiments of the present application may cooperatewith one another to be implanted into the lumen having the branch bloodvessels, thereby isolating the tumor body or the dissection,guaranteeing unblocked blood flow in the branch blood vessels andpreventing formation of the type-I endoleak.

The invention claimed is:
 1. A luminal stent graft, comprising: a firsttubular body and a second tubular body, wherein the second tubular bodyis sleeved outside the first tubular body, and at least one end of thesecond tubular body is sealingly connected with an outer surface of thefirst tubular body; the first tubular body comprises at least one firstradial supporting structure distributed along a circumferentialdirection of the first tubular body, the second tubular body comprises agraft covering at least one portion of the first tubular body, and asecond radial supporting structure which is arranged in a maximum radiallength region of the graft and surrounds the maximum radial lengthregion, and the second radial supporting structure has radialsupportability, wherein radial deformability of the second radialsupporting structure than that of the first radial supporting structure.2. The luminal stent graft according to claim 1, wherein, in a naturallyunfolded state, at a same position in a radial supporting section, aradial length of the second radial supporting structure is 1.3 times to3 times the radial length of the first radial supporting structure. 3.The luminal stent graft according to claim 1, wherein, in a naturallyunfolded state, a radial length of the second radial supportingstructure is more than that of the first radial supporting structure by2 mm to 30 mm.
 4. The luminal stent graft according to claim 1, whereinunder the action of a same radial force, a radial length variation ofthe second radial supporting structure is greater than that of the firstradial supporting structure; or under the action of a same radial force,a radial length change rate of the second radial supporting structure isgreater than that of the first radial supporting structure; or in caseof the same radial change rate or the same radial variation, a radialexternal force exerted on the first radial supporting structure isgreater than that exerted on the second radial supporting structure. 5.The luminal stent graft according to claim 1, wherein the second radialsupporting structure is a waveform ring-like object; and in a naturallyunfolded state, a maximum width m of any waveform of the waveformring-like object along a circumferential direction and a perimeter D ofthe second tubular body at the waveform accord with a condition that mis less than or equal to D/8.
 6. The luminal stent graft according toclaim 1, wherein the second radial supporting structure is of a meshedstructure comprising multiple grids; and in the naturally unfoldedstate, the maximum width m1 of any grid along the circumferentialdirection and the perimeter D of the second tubular body at the gridaccord with a condition that m1 is less than or equal to D/12.
 7. Theluminal stent graft according to claim 1, wherein in the portion coveredby a graft, the first tubular body further comprises a first graftcovering the first radial supporting structure.
 8. The luminal stentgraft according to claim 1, wherein one end of the graft is sealinglyconnected with the first tubular body, and the other end of the graft isopen; and the maximum radial length region of the graft is located nearto an opening of the open end, or is located at the middle portion ofthe graft.
 9. The luminal stent graft according to claim 1, wherein twoends of the graft are sealingly connected with the first tubular body,and the maximum radial length region of the graft is located at themiddle portion of the graft.
 10. The luminal stent graft according toclaim 1, wherein at least one end of the first tubular body has multipleconvex pieces extending in parallel to the longitudinal axis of thefirst tubular body, and a gap is reserved between two adjacent convexpieces.
 11. The luminal stent graft according to claim 1, wherein thefirst tubular body comprises four wave loops arrayed in sequence along alongitudinal central axis direction of the first tubular body, and thefour wave loops are connected through square connecting rings.
 12. Theluminal stent graft according to claim 1, wherein the first tubular bodycomprises barrel-shaped inner grafts, wave loops and annular outergrafts; the wave loops are arranged between the barrel-shaped innergrafts and the annular outer grafts in a clamping manner; and at leastpart of wave crests and/or wave troughs of the wave loops are exposedoutside.
 13. The luminal stent graft according to claim 1, wherein agraft is arranged on the first tubular body; and a hole penetratingthrough the graft is formed in a portion, which is near to an endportion of the first tubular body, on the graft or a wave loop, which isclose to the end portion of the first tubular body, of the first tubularbody is not completely covered by the graft.